全文获取类型
收费全文 | 362篇 |
免费 | 58篇 |
国内免费 | 19篇 |
专业分类
林业 | 109篇 |
农学 | 9篇 |
基础科学 | 17篇 |
23篇 | |
综合类 | 153篇 |
农作物 | 8篇 |
水产渔业 | 2篇 |
畜牧兽医 | 99篇 |
园艺 | 5篇 |
植物保护 | 14篇 |
出版年
2024年 | 1篇 |
2023年 | 6篇 |
2022年 | 3篇 |
2021年 | 16篇 |
2020年 | 13篇 |
2019年 | 25篇 |
2018年 | 19篇 |
2017年 | 30篇 |
2016年 | 28篇 |
2015年 | 16篇 |
2014年 | 27篇 |
2013年 | 15篇 |
2012年 | 39篇 |
2011年 | 27篇 |
2010年 | 15篇 |
2009年 | 14篇 |
2008年 | 12篇 |
2007年 | 15篇 |
2006年 | 12篇 |
2005年 | 11篇 |
2004年 | 6篇 |
2003年 | 7篇 |
2002年 | 5篇 |
2001年 | 5篇 |
2000年 | 8篇 |
1999年 | 7篇 |
1998年 | 8篇 |
1997年 | 5篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 6篇 |
1993年 | 8篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有439条查询结果,搜索用时 0 毫秒
11.
The increase in client willingness to pursue surgical procedures, the heightened perceived value of veterinary patients, and the desire to provide comprehensive medical care have driven the recent demand of using an integrative treatment approach in veterinary rehabilitation. Physical therapy following neurologic injury has been the standard of care in human medicine for decades, whereas similar rehabilitation techniques have only recently been adapted and utilized in veterinary medicine. Spinal cord injury is the most common neurologic disease currently addressed by veterinary rehabilitation specialists and will be the primary focus of this review; however, research in other neurologic conditions will also be discussed. Of particular interest, to clients and veterinarians are techniques and modalities used to promote functional recovery after neurologic injury, which can mean the difference between life and death for many veterinary patients.The trend in human neurologic rehabilitation, often regardless of etiology, is a multimodal approach to therapy. Evidence supports faster and improved recoveries in people after neurologic injury using a combination of rehabilitation techniques. Although the primary neurological disorders researched tend to be spinal cord injury, peripheral neuropathies, allodynia, multiple sclerosis, and strokes—many correlations can be made to common veterinary neurological disorders. Such comprehensive protocols entail gait training activities in combination with neuromuscular electrical stimulation and directed exercises. Additionally, pain-relieving and functional benefits are bolstered when acupuncture is used in addition to rehabilitation. Studies, both laboratory and clinical, support the use of acupuncture in the management of neurologic conditions in small animals, specifically in cases of intervertebral disc disease, other myelopathies, and neuropathic pain conditions. Acupuncture’s ability to promote analgesia, stimulate trophic factors, and decrease inflammation, including neuroinflammation, make it an alluring adjunct therapy after neurologic injury.Although there is limited research in veterinary medicine on physical techniques that expedite recovery after neurologic injury, there are sparse publications on clinical veterinary research suggesting the benefits of acupuncture, rehabilitation, and LASER in dogs with intervertebral disk disease. Accordingly, due to the relative lack of evidence-based studies in veterinary neurologic rehabilitation, much of the data available is human or laboratory-animal based, however, evidence supports the utilization of an early, comprehensive treatment protocol for optimal neurologic recovery. The rationale for why an integrative approach is critical will be detailed in this review; in addition, literature on specific physical rehabilitation techniques that have evidence of improved recoveries after neurologic injury, will be addressed. 相似文献
12.
13.
松针提取物药理作用研究进展 总被引:2,自引:0,他引:2
松针提取物富含维生素C、维生素E、类胡萝卜素、松针类黄酮、酚类化合物等生物活性物质,许多研究表明,松针提取物具有降血脂、抗氧化、抗炎、护肝、抗癌等作用。论文综述了近年来松针提取物的主要活性物质,以及主要药理作用研究进展,为进一步开发利用松针资源提供参考。 相似文献
14.
15.
多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是目前青春期、育龄期女性最常见的内分泌及代谢性疾病之一。由于排卵功能障碍使PCOS患者受孕率降低,且流产率增高,PCOS成为生育期妇女不孕的重要原因。杨正望教授对PCOS性不孕的病因病机及其中西医治疗均有其独到的见解,认为本病基本病机为“肾、脾、肝三脏功能失调为本,痰湿、瘀血形成为标”,数种病因病机常相互错杂,同时并存,导致多种症状同时出现,治疗上三因制宜,擅长运用中药、西药、针灸、耳穴压豆等多种方法综合治疗,临床疗效显著。 相似文献
16.
Urban derelict space can form a valuable complementary element to the formal green spaces of a city: wastelands are often biologically diverse and their unregulated status can provoke innovative spatial activities by a wide range of users. Using the case of an urban brownfield in Tallinn, Estonia, this paper examines how such a space is used and evaluates the magnitude of the impact of minor design interventions – so-called urban acupuncture – on the activities carried out by the users. The study used field observations and behaviour mapping to compare the spatial pattern of the users before and after small design interventions. Although there was widespread use beforehand there was both an increase in use and a different pattern afterwards, which was clearly detectable from the composite behaviour maps of both arrangements, where users follow the properties of the particular environment. The small improvements tested showed the largest effect on the female and the older user groups, raising the number of overall visits and increasing the occurrence of active behaviour almost five times. The research demonstrates that small, inexpensive and possibly temporary interventions can have a major positive effect. 相似文献
17.
Michael S. Watt David J. PalmerLindsay S. Bulman 《Forest Ecology and Management》2011,261(11):1792-1798
Despite being a damaging foliar disease of Pinus species little research has characterised spatial variation in disease severity of Dothistroma needle blight at a macroscale. Using an extensive dataset describing Dothistroma needle blight severity (Ssev) on plantation grown Pinus radiata stands distributed widely across New Zealand the objectives of this research were to (i) develop a regression model describing Ssev, (ii) use this model to identify key drivers of Ssev, their functional form and relative importance, and (iii) develop spatial predictions of Ssev for New Zealand P. radiata under current climate. Using an independent validation dataset, the final model accounted for 72% of the variance in Ssev using four significant (P < 0.001) explanatory variables and an isotrophic exponential model to account for the spatial covariance in the data. Ssev was most sensitive to mean air temperature from November to April (TNov-Apr), followed by mean relative humidity from October to April (RHOct-Apr), mean total November rainfall (PNov), and then stand age (A). There was a quadratic correlation between A and Ssev with Ssev increasing to a maxima at 12 years before declining. Ssev exponentially increased to a threshold with increases in both PNov and RHOct-Apr. The relationship between Ssev and TNov-Apr was quadratic with Ssev increasing to a maximum at TNov-Apr of 15.5 °C before declining at higher values of TNov-Apr. Spatial predictions of Ssev varied widely throughout New Zealand. Values of Ssev were highest in moderately warm wet environments in the North Island, and on the west coast of the South Island. In contrast, relatively low values of Ssev were predicted in drier eastern and southern regions of New Zealand. 相似文献
18.
19.
20.
针对连作障碍严重制约三七种植可持续发展的问题,设计一种针式水蒸气输出装置,对消毒针的结构参数进行优化,并通过土槽试验进行验证。通过Fluent软件对消毒针内部进行仿真,结果表明,消毒针出口流速、压力增大,出口温度无明显变化。土壤热传导试验表明,在5 min内即可将土壤加热到90℃,土壤加热基本规律为下层土壤加热效率较低、上层土壤加热效率高。为了探究消毒针不同结构参数对土壤升温效果的影响,选取单侧孔口数量、孔口直径和水蒸气出射角作为试验因素,选取土壤升温到90℃所需时间作为试验指标,进行了正交试验,确定消毒针最优结构参数组合为:消毒针单侧孔口数量为4个、孔口直径为2 mm、水蒸气出射角为45°,此时土壤升温到90℃时间最短,为116 s。通过Fluent多孔介质传热仿真得出,消毒针的最佳排布方式为6×6,最佳数量为36根,间距为250 mm。对消毒后的土壤有机质含量及pH值进行检测,表明消毒后土壤环境符合三七生长的环境要求。 相似文献